ATTENTION
(2022)Objective
Determine whether endovascular thrombectomy added to best medical care within 12 hours of acute basilar-artery occlusion is superior to best medical care alone.
Study Summary
• 90-day mortality lower with thrombectomy: 37% vs 55% (adjusted risk ratio 0.66, 95% CI 0.52-0.82).
• Symptomatic intracranial hemorrhage 5% (12 patients) with thrombectomy vs 0% control; procedural complications in 14% including one fatal arterial perforation.
Intervention
Endovascular thrombectomy (stent retriever, thromboaspiration, balloon angioplasty, stenting, and/or intraarterial thrombolysis) added to best medical care
Inclusion Criteria
Age ≥18 with moderate-to-severe acute ischemic stroke (NIHSS ≥10) from basilar-artery occlusion confirmed on CTA/MRA/DSA within 12 hours of estimated onset; prestroke mRS 0-2 (<80y) or 0 (≥80y); PC-ASPECTS ≥6 (<80y) or ≥8 (≥80y).
Study Design
Arms: Endovascular thrombectomy + best medical care vs best medical care alone (2:1 randomization)
Patients per Arm: 226 thrombectomy vs 114 control (ITT, N=340)
Outcome
• Excellent outcome (mRS 0-2) at 90 days 33% vs 11% (adjusted rate ratio 3.17, 95% CI 1.84-5.46); basilar patency at 24-72h 91% vs 38%.
• 90-day mortality 37% vs 55% (adjusted risk ratio 0.66, 0.52-0.82); symptomatic ICH 5% vs 0%; procedural complications 14%.
Clinical Question
In patients with acute ischemic stroke due to basilar-artery occlusion presenting within 12 hours, does endovascular thrombectomy added to best medical care improve 90-day functional outcomes compared with best medical care alone?
Bottom Line
In Chinese patients with acute basilar-artery occlusion presenting within 12 hours (about one-third receiving IV thrombolysis), endovascular thrombectomy roughly doubled the rate of good functional outcome (mRS 0-3) at 90 days and reduced 90-day mortality, at the cost of a 5% risk of symptomatic intracranial hemorrhage and 14% procedural complications.
Major Points
- Randomized 340 patients (2:1) at 36 centers in China to endovascular thrombectomy plus best medical care versus best medical care alone within 12 hours of estimated basilar-artery occlusion.
- Primary outcome (mRS 0-3 at 90 days) achieved in 46% (thrombectomy) vs 23% (control) — adjusted rate ratio 2.06 (95% CI 1.46-2.91, P<0.001).
- Ordinal shift toward better outcome favored thrombectomy (adjusted common odds ratio 2.87, 95% CI 1.84-4.47); mRS 0-2 at 90 days was 33% vs 11% (adjusted rate ratio 3.17, 95% CI 1.84-5.46).
- 90-day mortality was reduced with thrombectomy (37% vs 55%; adjusted risk ratio 0.66, 95% CI 0.52-0.82).
- Symptomatic intracranial hemorrhage occurred in 5% of thrombectomy patients vs 0% of controls; procedural complications occurred in 14%, including one fatal arterial perforation.
Study Design
- Study Type
- Randomized Controlled Trial
- Randomization
- Yes
- Blinding
- Open-label with blinded outcome assessment (structured telephone interview by locally certified neurologists or nurses unaware of treatment assignment); central imaging core lab and blinded clinical-event adjudication committee
- Sample Size
- 340
- Follow-up
- 90 days
- Centers
- 36
- Countries
- China
Primary Outcome
Definition: Good functional status (modified Rankin scale 0-3) at 90 days
| Control | Intervention | HR/OR | P-value |
|---|---|---|---|
| 23% (26/114) | 46% (104/226) | Rate ratio 2.06 (adjusted) (1.46-2.91) | <0.001 |
Limitations & Criticisms
- Exclusively Chinese population; large-artery atherosclerosis was the stroke cause in approximately 44% overall (intracranial LAA specifically ~36%, 123/340) — results may not generalize to Western populations with predominantly embolic basilar occlusion.
- Open-label design with unblinded treating teams; only outcome assessors were blinded.
- Relatively low use of IV thrombolysis (~31-34% vs ~80% in BASICS) partly due to Chinese out-of-pocket payment requirements, which may have disadvantaged the control group.
- Enrolled only patients with NIHSS ≥10; findings do not apply to milder posterior circulation stroke.
- No correction for multiple comparisons on secondary outcomes — secondary and subgroup results are exploratory.
- High rate of adjunctive angioplasty/stenting (40% intracranial, 8% extracranial) reflects local practice and may contribute to procedural complication rate.
- 12-hour window; findings do not apply to later time windows (see BAOCHE trial for 6-24h).
Citation
N Engl J Med 2022;387:1361-1372